Boeing has announced a successful test of the world's first hydrogen fuel-cell powered plane.
The two-seater Dimona aircraft took off on a series of test flights in Spain in February and March and stayed aloft for around 20 minutes, about half its current operational flight time.
The plane uses a combination of batteries and a proton exchange membrane fuel-cell for power.
Both systems are used for takeoff and climbing, but the batteries are shut down once the plane reaches its 3,300ft cruising altitude and the fuel-cell keeps the plane running at 100kph.
"Boeing is working to develop new technologies for environmentally progressive aerospace products," said Francisco Escarti, managing director at Boeing Research & Technology Europe.
"We are proud of our pioneering work during the past five years on the Fuel Cell Demonstrator Airplane project.
"It is a tangible example of how we are exploring future leaps in environmental performance, as well as a credit to the talents and innovative spirit of our team."
Boeing does not envisage fuel-cells ever being able to provide power for flight on large commercial aircraft.
But the company is looking at the possibility of integrating such technology into commercial flights to power instrumentation and auxiliary flight systems.
A key player in the programme was UK firm Intelligent Energy.
"Boeing's challenge to us was to provide a reliable and compact power system that could be integrated into such a light aircraft, and we delivered on our promise," said Henri Winand, chief executive at Intelligent Energy.
"This is a new dawn for clean aviation, and the latest project to vindicate our view that hydrogen fuel cells can find applications in a wide variety of sectors."
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